Photographic products and processes using metallic chelates



United States Patent 3,081,167 PHOTOGRAPHIC PRODUCTS AND PROCESSES USING METALLIC CHELATES Arthur B. Goulston, Roxbury, and Myron S. Simon,

Newton Centre, Mass, assignors to Polaroid Corporation. Cambridge. Mass, a corporation of Delaware No Drawing. Filed Jan. 26, 1959, Ser. No. 788,743 26 Claims. (CI. 9629) This invention relates to photography and, more particular y, to improvements in photographic diffusiontransfer reversal processes for obtaining color images.

, A principal object of the present invention is to provide novel processes wherein developing agents capable of developing a latent image and imparting a reversed or positive colored image of said latent image to a superposed image-receiving material are stabilized subsequent to formation of said positive colored image.

Another object is to provide novel processes suitable for use in preparing stabilized monochromatic and multichromatic photographic images.

A further object is to increase the stability of positive diffusion-transfer colored images against the deleterious effects of actinic radiation.

A still further object is to increase the stability of positive diffusion-transfer colored images against the deleterious effects of humidity and/ or temperature variations.

A still further object is to stabilize transferred d e in a diffusion-transfer image-receiving element by complexing said dye with an appropriate metal.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the processes involving the several steps and the relation and order of one or more of such steps with respect to each of the others, and the products possessing the features, properties and the re ation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

The copending application of Howard G. Rogers, Serial No. 748.421, filed July 14, 1958, and now U.S. Patent 2,983,606 issued May 9, 1961, a continuation-inpart of Serial No. 415.073, filed March 9, 1954 (now abandoned), discloses diffusion-transfer reversal processes wherein a photographic negative material, such as a photographic element comprising an exposed silver halide emulsion layer containing a latent image, is processed using a dye developer to impart to an image-receiving element a reversed or positive dye image of said latent image by permeating into said emulsion layer a suitable 3,081,167 Patented Mar. 12, 1963 position permeates the emulsion to provide a solution of dye developer substantially uniformly distributed therein. As the latent image is developed, the oxidation product of the dye developer is immobilized or precipitated in situ with the developed silver, thereby providing an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition. This immobilization is apparently, at least in part, due to a change in the solubility characteristics of the dye developer upon oxidation, and especially as regards its solubility in alkaline solutions. It may also be due, in part, to a tanning effect on the emulsion by the oxidized developing agent. At least part of this imagewise distribution of unoxidized dye developer is transferred, by imbibition, to a superposed image-receiving layer or element, said transfer substantially excluding silver or oxidized dye developer. The latter element receives a depthwise diffusion, from the emulsion, of unoxidized mobile dye developer Without appreciably disturbing the imagewise distribution thereof to provide a reversed or positive, colored image of the developed image. If the color of the diffused dye developer is affected by changes in the pH of the image-receiving element, this pH may be adjusted in accordance with well-known techniques to provide a pH affording the desired color. Imbibition periods of approximately one minute have been found to give good results, but this contact period may be adjusted where necessary to compensate for variations in temperature or other conditions. The desired, positive image is revealed by stripping the image-receiving element from the photo-- sensitive element at the end of the imbibition period.

The aforementioned dye developers may be utilized in the photosensitive e ement, for example in, on or behind the silver halide emulsion, or they may be utilized in the image-receiving element or in the liquid processing composition. In a preferred embodiment, a coating or layer of the dye developer is placed behind the silver halide emulsion, i.e.,'on the side of the emulsion adaptedto be located most distant from the photographedsubject when th emulsion is exposed and preferably also adapted to be most distant from the image-receiving elementwhen in superposed relationship therewith. Placing the dye liquid processing composition and bringing said emulsion layer into superposed relationship image-receiving layer.

In carrying out the processes of this invention, a photosensitive element containing a silver halide emulsion is exposed and wetted with a liquid processing composition, for example, by immersing, coating, spraying, flowing, etc., in the dark, and the photosensitive element superposed, prior to, during or after wetting, on a sheetlike support element, which may be utilized as an image-receiving element. sensitive element contains a layer of dye developer, and the liquid processing composition is applied to the photosensitive element in a uniform layer as the photosensitive element is brought into superposed position with an image-receiving element. It is also within the scope of this invention to apply the liquid processing composition prior to exposure, in accordance with the disclosure in the copending application of Edwin H. Land, Serial No. 498,672, filed April 1, 1955. The liquid processing comwith an appropriate developer behind the emulsion layer, as in the preferredembodiment, has the advantage of providing increased contrast in the positive image, and also minimizes any" light-filtering action by the colored dye developer. In this preferred embodiment, the layer of dye developermay be applied by using a coating solution containing about 0.5 to 8%, by weight, of the dye developer. Simi-' lar concentrations may be used if the dye developer is utilized as a component of the liquid processing corn position, concentrations as low as 0.2% in the liquid processing composition being suitable in certain instances.

The liquid processing composition above referred to comprises at least an aqueous solution of an alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate, and may contain the dye developer. In some instances, it may contain a minor amount of'a conventional developing agent. If the liquid processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin, uniform layer, it may also include a viscosity-increasing compound constituting the film-forming material of the type which, when said composition is spread and dried, will form a relatively firm and relatively stable film. A preferred film-forming material is a high molecular weight polymer such as a polymeric, water-soluble ether inert to an alkali solution, as, for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other film-forming materials or thickening agents whose ability to increase viscosity is substantially unaffected when left in solution for a long period of time may also be usedf It has been discovered that certain dyes, i.e., monoand disazo dyes which contain hydroxyl or carboxyl radicals, substituted on aryl nuclei in positions ortho and ortho' to at least one azo group, preferably those azo dyes which comprise dye developers, i.e., dyes which possess a silver halide developing function, have unique properties in that said dyes may be stabilized against the color degradation effects or" actinic radiation, humidity and/or temperature variations by appropriate metallization, i.e., metal complexing said dyes with a copper, nickel or cobalt ion, subsequent to transfer of mobile dye to a superposed image-receiving element.

In general, the aforementioned complexing may be accomplished as a result of contacting the appropriate dye with a nickel, copper or cobalt salt and/or an appropriate nickel or copper chelate, for example, a nitrate, suliiate, oxalate, etc., salt and/or a chelate of the formula:

wherein R is selected from the group consisting of hydrogen, aliphatic and aromatic groups; R is selected from the group consisting of aliphatic and aromatic groups; X and Y each may be the same or different and are selected from the group consisting of -O- and =NOH groups; and Z is a metallic atom selected from the group consisting of copper and nickel; for example, a nickel or copper chelate of an enolizable B-diketone, such as acetylacetone, an enolizable S-keto ester, such as ethyl acetoacetate, an enolizable fi-ketoxirne, such as dibenzoylmethane monoxime, or a fi-ketoaldehyde; subsequent to transfer of the image-forming dye to a superposed image-receiving element. The contact may be accomplished by any of the varied procedures known to the photographic art, for example, in diffusion-transfer reversal processes, the metallic salt and/or chelate may be dis- .persed within and/or disposed in a separate layer superposed on the respective image-receiving elements such that transferred dye contacts said metallic salt and/or chelate on and/or Within said receiving layer to form the desired complex thereon and/ or therein. The metallic salt and/or chelate may also be disposed in an appropriate processing solution, for example where desirable, the image-receiving element may be contacted with a solution of the metallic salt and/or chelate subsequent to formation of the desired image as well as subsequent to displacement of the image-receiving element from its superposed relation to a photosensitive negative element.

It is to be understood that the process utilized may comprise in whole or in part one or more of the previously enumerated procedures to suit the requirements of the operator.

A preferred procedure has been determined to be that of dispersing an appropriate metal chelate within the image-receiving element.

It should be noted that it is within the scope of this invention to form images which comprise mixtures of complexed and uncomplexed dyes and to effect complexing either at room temperatures or at an artificially designated temperature, as for example, complexing at elevated temperatures.

Although the illustrative photographic processes herein detailed employ the dye developer techniques disclosed in the aforementioned copending US. application, Serial No. 748,421, it will be apparent that the several features comprising the herein disclosed inventive concepts are equally applicable to diffusion-transfer processes utilizing, as image-forming components, coupling dyes, that is, complete dyes which possess: (1) at least one ortho, ortho'-dihydroxy azo group and (2) a coupling function. These dyes react with the oxidation product of a color developer to provide the desired positive image formation according to the processes disclosed in US. Patent No. 2,774,668, issued December 18, 1956, to Howard G. Rogers, and the copending US. application of Howard G. Rogers, Serial No. 613,691, filed October 3, 1956. In addition, the concepts herein disclosed are applicable to diffusion-transfer processes wherein the formation of an imagewise distribution of dye components is controlled by the concentration of alkali present, as for example, the alkali exhaustion transfer processes disclosed in the copending US. application of Edwin H. Land, Serial No. 640,821, filed February 18, 1957. The aforementioned concepts are also applicable to processes wherein the transfer of the dye is controlled by a physically and/or chemically induced matrix obstruction as, for example, by differential tanning or hardening of a dye carrier and/or light-sensitive stratum, such as employed in im-' bibition dyeing processes.

The invention will be illustrated in greater detail in conjunction with the following specific examples which set out representative utilizations of the novel photographic processes of this invention which, however, are not limited to the details therein set forth and are intended to be illustrative only. In the following examples all parts are given by weight except where otherwise noted, and all operations involving lightsensitive materials are carried out in the absence of actinic radiation.

Example 1 Monochrome photographic prints may be prepared according to the following procedure.

A photosensitive element is prepared by coating 2. gelatin-coated film base with a solution containing 4% of 2-hydroxynaphthalenazo-hydroquinone, which is disclosed in the copending US. application of Elkan R. Blout, Saul G. Cohen, Milton Green, and Myron S. Simon, Serial No. 755,804, filed August 18, 1958, a continuationin-part of application Serial No. 450,208, filed August 16, 1954 (now abandoned), in a 4% solution of cellulose acetate hydrogen phthalate in a 50:50 mixture, by volume, of acetone and tetrahydrofuran. After this coating has dried, a silver iodobromide emulsion is applied. This photosensitive element is exposed and processed by spreading an aqueous liquid processing composition comprising:

Percent Sodium carboxymethyl cellulose 3.5 1-phenyl-3-pyrazolidone 0.1 Sodium hydroxide 2.0 2,S-bis-ethyleneiminohydroquinone 0.3 6-nitrobenzimidazole 0.24

between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetate-coated baryta paper which has been coated with a solution comprising 10% Nylon Type F8 (trade name of E. I. du Pont de Nemours & Co., Wilmington, Delaware, for N-methoxymethyl polyhexamethylene adipamide) in aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a magenta dye image of the photographed subject.

Example 2 A monochrome print prepared according to the procedure stated in Example 1 is exposed to a 275 watt sunlamp at a distance of ca. 20 inches for 72 hours.

Densimetric measurement of the accelerating fading test on the dye image showed a loss of density, e.g., from a density of 2.30 to a density of 1.05.

Example 3 A monochrome print is prepared according to the procedure stated in Example 1.

The resultant print, containing a magenta dye image of the photographed subject, is swabbed with an approximately 0.5% solution of bis-(acetylacetono) copper (II) in a 50:50 solution, by volume, of water and methanol and exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The copper-complexed dye image exhibits substantially no degradation due to the heat and actinic radiation of the aforementioned procedure.

Example 4 A monochrome print is prepared according to the following procedure.

A photosensitive element is prepared according to the procedure stated in Example 1. This photosensitive elementis exposed and processed by spreading the liquid processing composition of Example 1 between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5% or bis-acetylacetono) copper (II) and 4% Nylon Type F8 in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed reversed positive dye image of the photographed subject.

The resultant print, containing the complexed dye image of the photographed subject, exhibits an initial density substantially equivalent to the noncomplexed dye images of Example 1 and is exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The copper-complexed dye image exhibits substantially no degradation due to the heat and actinic radiation of the aforementioned procedure.

Example 5 A monochrome print is prepared according to the procedure stated in Example 1.

The resultant print, containing a magenta dye image of the photographed subject, is swabbed with an approximately 0.5% solution of bis-(ethylacetoacetato) copper (II) in a 50:50 solution, by volume, of Water and metham] and exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The copper-complexed dye image exihibits substantially no degradation due to the heat and actinic radiation of the aforementioned procedure.

Example 6 A monochrome print is prefared according to the following procedure. g

A photosensitive element is prepared according to the procedure stated in Example 1. This photosensitive element is exposed and processed by spreading the liquid processing composition of Example 1 between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5% of bis-(ethylacetoacetato) copper (II) and 4% Nylon Type F8 in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed reversed positive dye image of the photographed subject.

The resultant print, containing the complexed dye image of the photographed subject, exhibits an initial density substantiallyequivalent to the noncomplexed dye images 'of Example 1 and is exposed to heat and actinic rediation according to the procedure disclosed in Example 2.

The copper complexed dye image exhibits substantially no degradation due to the heat and actinic radiation of the aforementioned procedure.

6 Example 7 Monochrome photographic prints may be prepared according to the following procedure.

A photosensitive element is prepared by coating a gelatin-coated film base with a solution containing 4% of l- (4' [,8-(hydroquinonyl)-ethyl]-2'-hydroxy-phenylazo)-2- naphthol, which is disclosed in the copending US. application of Milton Green and Myron S. Simon, Serial No. 788,893, filed concurrently herewith, in a 4% solution of cellulose acetate hydrogen phthalate in a 50:50 mixture, by volume, of acetone and tetrahydrofuran. After this coating has dried, a silver iodobromide emulsion is applied. This photosenstive emulsion is exposed and processed according to the procedure of Example 1. After an imbibition period of approximately one minute, the image-receiving element is separated and contains an orange-red dye image of the photographed subject.

Example 8 A monochrome print prepared according to the procedure stated in Example 7, is exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

Examination of the print after the accelerated fading test showed that substantial fading had occurred.

Example 9 A monochrome print is prepared according to the following procedure.

A photosensitive element is prepared according to the procedure stated in Example 7. This photosensitive element is exposed and processed by spreading the liquid processing composition of Example 1 between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5% of bis-(ethylacetoacetato) copper (II) and 4% Nylon Type F8 in aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed reversed positive dye image of the photographed subject. 1 The resultant print, containing the complexed dye image of the photographed subject, exhibits an initial density substantially equivalent to the nonconplexed dye images of Example 7 and is exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The copper-complexed dye image exhibits substantially no degradation due to the heat and actinic radiation of the aforementioned procedure.

Example! 10 A monochrome print is prepared according to the procedure stated in Example 1.

The resultant print, containing a magenta dye image of the photographed subject, is swabbed with an approximately 0.5 solution of bis-(trifluoroacetylacetono) copper (II) in a 50:50 solution, by volume, of water and methanol and exposed to heat and act nic radiation according to the procedure disclosed in Example 2.

The purple copper-complexed dye image exhibits sub? stantially no degradation due to the heat and actinic radiation of the aforementioned procedure.

Example 11 A monochrome print is prepared according to the following procedure. 7

A photosensitive element is prepared according to the procedure stated in Example 1. This photosensitive element is exposed and processed by spreading the liquid processing composition of Example 1 between said photo sensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5% of bis-(trifiuoroacetyl acetono) copper (II) and 4% Nylon Type F8 in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed reversed positive purple dye image of the photographed subject.

The resultant print, containing the complexed dye image of the photographed subject, exhibits an initial density substantially equivalent to the noncomplexed dye images of Example 1 and is exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The copper-complexed dye image exhibits substantially no degradation due to the heat and actinic radiation of the aforementioned procedure.

Example 12 A monochrome print is prepared according to the procedure stated in Example 1.

The resultant print, containing a magenta dye image of the photographed subject, is swabbed with an approximately 0.5% solution of bis-(salicylaldoximo) copper (II) in a water-methanol solvent and exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The copper-complexed dye image exhibits increased stability against the degradation eifects of exposure to the heat and actinic radiation of the aforementioned procedure.

Example 13 A monochrome print is prepared according to the following procedure.

A photosensitive element is prepared according to the procedure stated in Example 1. This photosensitive element is exposed and processed by spreading the liquid processing composition of Example 1 between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5% of bis-(salicylaldoximo) copper (II) and 4% Nylon Type F8 in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed reversed positive dye image of the photographed subject.

The resultant print, containing the complexed dye image of the photographed subject, exhibits increased stability against the degradation effects of exposure to the heat and actinic radiation of the accelerated aging test procedure disclosed in Example 2.

Example 14 A monochrome print is prepared according to the procedure stated in Example 1.

The resultant print, containing a magenta dye image of the photographed subject, is swabbed with an approximately 0.5% solution of bis-(ethylacetoacetato) nickel (II) in a water-methanol solvent and exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The nickel-complexed dye image exhibits increased stability against the degradation effects of exposure to the heat and actinic radiation of the aforementioned procedure.

Example 15 A monochrome print is prepared according to the following procedure.

A photosensitive element is prepared according to the procedure stated in Example 1. This photosensitive element is exposed and processed by spreading the liquid processing composition of Example 1 between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The

image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5% of bis(ethylacetoacetato) nickel (II) and 4% Nylon Type F8 in aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed reversed positive dye image of the photographed subject.

The resultant print, containing the complexed dye image of the photographed subject, exhibits increased stability against the degradation effects of exposure to the heat and actinic radiation of the accelerated aging test procedure disclosed in Example 2.

Example 16 A monochrome print is prepared according to the procedure stated in Example 1.

The resultant print, containing a magenta dye image of the photographed subject, is swabbed with an approximately 0.5% solution of bis-(acetylacetono) nickel (II) in a Water-methanol solvent and exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

The nickel-complexed dye image exhibits increased stability against the degradation effects of exposure to the heat and actinic radiation of the aforementioned procedure.

Example 17 A monochrome print is prepared according to the following procedure.

A photosensitive element is prepared according to the procedure stated in Example 1. This photosensitive element is exposed and processed by spreading the liquid processing composition of Example 1 between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5 of bis-(acetylacetono) nickel (II) and 4% Nylon Type F8 in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed reversed positive dye image of the photographed subject.

The resultant print, containing the complexed dye image of the photographed subject, exhibits increased stability against the degradation effects of exposure to the heat and actinic radiation of the accelerated aging test procedure disclosed in Example 2.

Example 18 Monochrome photographic prints may be prepared according to the following procedure.

A photosensitive element is prepared by coating a gelatin-coated film base with a solution containing 3% of 4- acetyl 2 (4' [p (hydroquinonyl) ethyl] 2 hydroxy-phenylazo)-1-naphthol, which is disclosed in the copending US. application of Milton Green and Myron S. Simon, Serial No. 788,893, filed concurrently herewith, in a 2% solution of cellulose acetate hydrogen phthalate in a 50:50 mixture, by volume, of acetone and tetrahydrofuran. After this coating has dried, a silver iodobromide emulsion is applied. This photosensitive emulsion is exposed and processed according to the procedure of Example 1 with an aqueous liquid processing composition comprising:

Percent Sodium carboxymethyl cellulose 4.5 1-phenyl-3-pyrazolidone 0.6 Sodium hydroxide 2.0 2,5-bis-ethyleneiminohydroquinone 0.4 6-nitrobenzimidaz0le 0.12

After an imbition period of approximately one minute,

the image-receiving element is separated and contains an orange-red dye image of the photographed subject.

Example 19 A monochrome print prepared according to the procedure stated in Example 18 is exposed to heat and actinic radiation according to the procedure disclosed in Example 2.

Examination of the print after the accelerated fading test showed that substantial fading had occurred.

Example 20 A monochrome print is prepared according to the following procedure.

A photosensitive element is prepared according to the procedure stated in Example 18. This photosensitive element is exposed and pnocessed by spreading the liquid processing composition of Example 18 between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetatecoated baryta paper which has been coated with a solution comprising approximately 0.5% bis-(acetylaceton-o) copper (II) and 4% Nylon Type F8 in 80% aqueous isopropanol. After an imbibition period of approximately one minute, the image-receiving element is separated and contains a copper-complexed magenta dye image of the photographed subject.

, The resultant print, containing the complexed dye image, exhibits increased stability against the degradation eifects of exposure to ithe heat and actinic radiation of the accelerated aging test procedure disclosed in Example 2.

While processes of the present invention have been described above, it is to be understood that these processes may be modified in many ways without departing from the scope of the invention.

it will be noted that the liquid processing compositions may, and in the above examples do, contain a small amount of an auxiliary or accelerating developer, such as metol, amidol, benzylaminophenol, or a 3-pyrazolidone, such as l-phenyl-3-pyrazolidone. This auxiliary developer serves to accelerate'and possibly initiate the action of the dye developer. veloper oxidized in exposed areas may have been oxidized by an energy transfer reaction With oxidized auxiliary developer.

The azo dye developers are preferably selected with a view to their usefulnessin color photography and, in particular, their ability to provide the desired subtractive colors, i.e., magenta, yellow or cyan, in diffusion-transfer reversal processes utilizing color screen, bipack and tripack photographic procedures.

It will be apparent that, by appropriate selection of the image-receiving element from among suitable known opaque and transparent materials, it is possible to obtain either a colored positive reflection print or a colored posi tive transparency. Likewise, the inventive concepts herein set forth are adaptable for multicolor work by the use of special photographic materials, for example, film materials of the type containing two or more photosensitized elements associated with an appropriate number of imagereceiving elements and adapted to be treated with one or more liquid processing compositions, appropriate dye developers suitable to provide the desired subtractive colors being incorporated in the photosensitized elements or in the liquid processing compositions. Examples of such photographic materials are disclosed in US. Patent No. 2,647,049 to Edwin H. Land.

The inventive concepts herein set forth are also adaptable for the formation of stabilized colored images in accordance with the photographic products and processes described and claimed in the copending application of Edwin H. Land, Serial No. 448,441, filed August 9, 1954,

It is possible that some of the dye de- 10 now US. Patent 2,968,554, issued January 17, 1961, and also the copending application of Edwin H. Land and Howard G. Rogers, Serial No. 565,135, filed February 13, 1956. 1

In the preceding portions of the specification the expression color has been frequently used. This expression is intended to include the use of a plurality of colors to obtain black, as Well as the use of a single black dye developer.

Although the illustrative photographic processes herein detailed employ monoand disazo dyes which contain hydroxy or carboxyl radicals substituted on aryl nuclei in positions ortho and ortho to at least one azo group and preferably chelating agents within the previously set forth formula, it will be apparent that the several features comprising the herein disclosed inventive concepts are equally applicable to diffusion-transfer processes employing, as image dyes, one or more dyes which contain at least one metallizable configuration or group as well as to diffusion-transfer processes employing, as metal atom donor, a metal ohelate exhibiting less intermolecular bond ing stability than the metal dye complex ultimately formed.

The copending US. application of Myron S. Simon, Serial No. 788,786, filed concurrently herewith, contains claims directed to photographic transfer processes wherein monoand disazo dye developers which contain hydroxyl or carboxyl radicals substituted on aryl nuclei in positions ortho and ortho to at least one azo group are metal complexed, subsequent to transfer to an imagereceiving element, by contacting said dye developers with a metallic ion selected from the group consisting of cop per, nickel and cobalt ions and specified products for utilization in such processes.

Since certain changes may be made in the above products and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In a process of forming a photographic image, the steps which comprise developing'a latent image contained in an exposed silver halide emulsion with a processing solution containing a dye, selected from the group consisting of monoand disazo dyes, characterized in that said dye contains, substituted at positions ortho and ortho to an azo link, a group selected from the group consisting of hydroxyl and carboxyl groups, immobilizing said dye in exposed areas, providing in said emulsion a predetermined distribution of mobile dye and trans ferring at least part of said distribution of said mobile dye, by imbibition, from said emulsion to an image-receiving element in superposed relationship with said emulsion, contacting at least part of said transferred dye with at least one chelate selected from the group con: sisting of .chelatcs within the formula:

wherein R is selected from the group consisting of hydrogen, aliphatic and aromatic groups; R is selected from the group consisting of aliphatic and aromatic groups; X and Y are each selected from the group consisting of O- and =N-OH groups; and Z is a metallic atom selected from the group consisting of copper and nickel; complexing thereby at least part of said transferred dye to impart to said image-receiving element a reversed, at least in part metal-complexed, dye image of the developed image.

2. The process as defined in claim 1 wherein said chelate comprises an enolizable fi-diketone copper chelate.

3. The process as defined in claim 1 wherein said chelate comprises bis-(acetylacetono) copper (II).

4. The process as defined in claim 1 wherein said chelate comprises bis-(ethylacetoacetato) copper (II).

5. The process as defined in claim 1 wherein said chelate comprises bis- (trifiuoroacetylacetono) copper (II).

6. The process as defined in claim 1 wherein said chelate comprises bis-(salicylaldoximo) copper (II).

7. The process as defined in claim 1 wherein said chelate comprises bis-(ethylacetoacetato) nickel (II).

8. The process as defined in claim 1 wherein said chelate comprises bis-(acetylacetono) nickel (II).

9. The process as defined in claim 1 wherein said chelate is disposed in a separate layer superposed on said image-receiving element and the metal-complexed dye image is formed by permeating said layer with said transferred dye.

10. The process as defined in claim 1 wherein said chelate is dispersed in said image-receiving element and the metal-complexed dye image is formed by permeating said element with said transferred dye.

11. The process as defined in claim 1 wherein said chelate is disposed in a processing solution and the metal dye complex is formed by contacting said solution with said transferred dye containing image-receiving element.

12. The process as defined in claim 11 wherein said processing composition is contacted with said transferred dye containing image-receiving element subsequent to dissociation of said image-receiving element from its superposed relation to said silver halide emulsion.

13. The process as defined in claim wherein said metalcomplexed dye image comprises a nickel-complexed 2- hydroxynaphthaleneazohydroquinone image.

14. A photographic product for receiving a color image which comprises an image-receiving element comprising a support, a dye-receiving layer on said support, and at least one chelate in a layer on the same side of said support as said dye-receiving layer, said chelate being of the formula:

wherein R is selected from the group consisting of hydrogen, aliphatic and aromatic groups; R is selected from the group consisting of aliphatic and aromatic groups; X and Y are each selected from the group consisting of O-- and =NOH groups; and X is a metallic atom selected from the group consisting of copper and nickel.

15. A photographic product as defined in claim 14 wherein said chelate comprises an enolizable /3-diketone copper chelate.

16. A photographic product as defined in claim 14 wherein said chelate comprises bis-(acetylacetono) copper (II).

17. A photographic product as defined in claim 14 wherein said chelate comprises bis-(ethylacetoacetato) copper (II).

18. A photographic product as defined in claim 14 wherein said chelate comprises bis-(trifiuoroacetylacetone) copper (II).

19. A photographic product as defined in claim 14 wherein said chelate comprises bis- (salicylaldoximo) copper (II).

20. A photographic product as defined in claim 14 wherein said chelate comprises bis-(ethylacetoacetato) nickel (II).

21. A photographic product as defined in claim 14 wherein said chelate comprises bis-(acetylacetono) nickel (II).

22. A photographic product as defined in claim 14 wherein said dyeable layer comprises a layer of N-methoxymethyl polyhexamethylene adipamide.

23. A photographic product as defined in claim 14 wherein said chelate is dispersed within said dyeable layer.

24. A photographic product as defined in claim 14 wherein said chelate is disposed in a separate layer superposed on said dyeable layer.

25. The process as defined in claim 1, wherein said dye comprises a dye developer, said dye developer being a compound which is both a dye and a silver halide developing agent, said dye developer further being selected from the group consisting of monoand disazo dye dcvelopers substituted at positions ortho and ortho to an azo linkage with a group selected from the group consisting of hydroxyl and carboxyl groups.

26. In a process of forming photographic images by diffusion-transfer processes, the step which comprises contacting, subsequent to transfer image formation, an image dye possessing at least one metallizable group, with a chelate exhibiting less intermolecular bonding stability than the metal image dye complex ultimately formed, complexing thereby at least part of said image dye to impart to an image-receiving element a dye image, at least in part metal-complexed, of the photographed subject.

References Cited in the file of this patent UNITED STATES PATENTS 2,559,643 Land July 10, 1951 2,774,668 Rogers Dec. 18, 1956 2,983,606 Rogers May 9, 1961 FOREIGN PATENTS 779,621 Great Britain July 24, 1957 804,971 Great Britain Nov. 26, 1958 OTHER REFERENCES Martell et al.: Chemistry of the Metal Chelate Compounds, Prentice-I-Iall, N.I., 1956, pp. 495-499, 510 and 549-551.

Venkataraman: The Chemistry of Synthetic Dyes, I, Academic Press, Inc., New York, 1952, pages 5523.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,081,167 March 12, 1963 Arthur B, Goulston et a1,

It is hereby certified that error appears in the above numbered pat ent requiring correction and that the said Letters Patent should read as corrected below.

Column 2, line 40, for "th" read the column 5, line 22, for "bis-acetylacetono)" read bis-(acetylacetono) line 52, for "prefared" read prepared column 7, line 3, for "acetyl acetono)" read acetylacetono) column 10, line 12, for "hydroxy" read hydroxyl column 11, line 32, after "claim" insert 1 Signed and sealed this 12th day of Nov ember 1963.

(SEAL) Attest:

ERNEST W. SWIDER EDWIN L. REYNOLDS Attesting Officer Ac ti ng Commissioner of Patents 

1. IN A PROCESS OF FORMING A PHOTOGRAPHIC IMAGE, THE STEPS WHICH COMPRISE DEVELOPING A LATENT IMAGE CONTAINED IN AN EXPOSED SILVER HALIDE EMULSION WITH A PROCESSING SOLUTION CONTAINING A DYE, SELECTED FROM THE GROUP CONSISTING OF MONO- AND DISAZO DYES, CHARACTERIZED IN THAT SAID DYE CONTAINS, SUBSTITUTED AT POSITIONS ORTHO AND ORTHO'' TO AN AZO LINK, A GROUP SELECTED FROM THE GROUP CONSISTING OF HYDROXYL AND CARBOXYL GROUPS, IMMOBILIZING SAID DYE IN EXPOSED AREAS, PROVIDING IN SAID EMULSION A PREDETERMINED DISTRIBUTION OF MOBILE DYE AND TRANSFERRING AT LEAST PART OF SAID DISTRIBUTION OF SAID MOBILE DYE, BY IMBIBITION, FROM SAID EMULSION TO AN IMAGE-RECEIVING ELEMENT IN SUPERPOSED RELATIONSHIP WITH SAID EMULSION, CONTACTING AT LEAST PART OF SAID TRANSFERRED DYE WITH AT LEAST ONE CHELATE SELECTED FROM THE GROUP CONSISTING OF CHELATES WITHIN THE FORMULA: 